Optical fiber technology is well suited for communications applications because optical fibers have a wide transmission bandwidth and relatively low attenuation. However, optical fiber interfaces to electronic and optical networks are expensive to manufacture because of the difficulty associated with mounting laser transmitting and receiving devices onto substrates and aligning them with separately mounted optical fibers. Additionally, high performance applications of optical fiber technology present integration challenges, particularly at optical-electrical boundaries, from cost, technological and miniaturization perspectives. For these reasons, fiber optic interfaces have been a barrier that has slowed the penetration of fiber optic technology into local metropolitan area communication systems and other markets.
Conventional interfaces, such as transmitter optical sub-assembly (TOSA) and receiver optical sub-assembly (ROSA) interfaces for high speed applications have had a relatively large footprint and have not incorporated cost effective technologies, such as vertical cavity surface emitting lasers (VCSELs). Rather, conventional TOSA/ROSA packages have incorporated edge emitting laser technologies. For example, a package design known as a butterfly package is in wide use today for TOSA/ROSA applications. The butterfly packages does not permit the use of VCSEL technology, is relatively large and does not incorporate electrically conductive signal traces and RF design features which would allow this package to operate at high speeds.
Accordingly, there is a need for a compact optical assembly that operates in the high-speed arena. There is a further need for a compact optical assembly that incorporates VCSEL technology and RF design features that permit high speed operation. There is a further need for a serial optical assembly that is easy to manufacture, assemble and use that can incorporate off the shelf components to achieve a low overall cost of manufacture and deployment. There is still a further need for an assembly that deploys VCSEL technology in the high-speed arena, such as 10 Gigabit per second serial applications.